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OBJECTIVE: These days, the gold standard procedure for otosclerosis treatment is stapes surgery. The endoscopic approach of the procedure is gaining popularity as endoscopic ear surgery develops across the globe. The main objective of this study is to gather and compile well-documented and reliable data regarding surgical outcomes for the endoscopic approach to stapes surgery up to this date. MATERIALS AND METHODS: Publications in English were searched in the PUBMED/MEDLINE database and were systematically reviewed. A total of 16 articles were reviewed according to the inclusion criteria, obtaining a total of 573 patients managed surgically for otosclerosis, using an endoscopic approach. Data were systematically extracted and compared across variables. RESULTS: Data were obtained as follows: mean age of 43 years; female proportion of 60%; 3 mm endoscope diameter of 51%, 4 mm of 39%; titanium piston-type prostheses of 52% and Teflon of 48%; length of the prosthesis (mode) was 4.5 mm; 0.6 mm diameter of the piston of 81% and 0.4 mm of 19%; mean surgical time was 55 min. Hearing results, mean preoperative air-bone gap (ABG) 31 dB; mean postoperative ABG 9 dB; ABG improvement of 22 dB; an ABG closure rate to 20 dB or less of 92% and an ABG closure rate to 10 dB or less of 77%. Complication rates: intraoperative tympanic membrane perforation of 5%; postoperative vertigo of 11%; postoperative dysgeusia of 10%; reported a postoperative neurosensorial hearing loss of 0.2%; reported gusher phenomenon of one case (0.2%). CONCLUSION: Endoscopic stapes surgery is completely achievable using 0º angle and 4-mm-diameter sinus surgery endoscope. Instrument availability should not be an obstacle to the development of this type of surgery in any otolaryngology department. Audiological outcomes are comparable to microscopic approaches.
Assuntos
Prótese Ossicular , Otosclerose , Cirurgia do Estribo , Adulto , Endoscopia , Feminino , Humanos , Otosclerose/cirurgia , Estudos Retrospectivos , Estribo , Cirurgia do Estribo/efeitos adversos , Resultado do TratamentoRESUMO
Birds are hosts for several zoonotic pathogens. Because of their high mobility, especially of longdistance migrants, birds can disperse these pathogens, affecting their distribution and phylogeography. We focused on Borrelia burgdorferi sensu lato, which includes the causative agents of Lyme borreliosis, as an example for tick-borne pathogens, to address the role of birds as propagation hosts of zoonotic agents at a large geographical scale. We collected ticks from passerine birds in 11 European countries. B. burgdorferi s.l. prevalence in Ixodes spp. was 37% and increased with latitude. The fieldfare Turdus pilaris and the blackbird T. merula carried ticks with the highest Borrelia prevalence (92 and 58%, respectively), whereas robin Erithacus rubecula ticks were the least infected (3.8%). Borrelia garinii was the most prevalent genospecies (61%), followed by B. valaisiana (24%), B. afzelii (9%), B. turdi (5%) and B. lusitaniae (0.5%). A novel Borrelia genospecies "Candidatus Borrelia aligera" was also detected. Multilocus sequence typing (MLST) analysis of B. garinii isolates together with the global collection of B. garinii genotypes obtained from the Borrelia MLST public database revealed that: (a) there was little overlap among genotypes from different continents, (b) there was no geographical structuring within Europe, and (c) there was no evident association pattern detectable among B. garinii genotypes from ticks feeding on birds, questing ticks or human isolates. These findings strengthen the hypothesis that the population structure and evolutionary biology of tick-borne pathogens are shaped by their host associations and the movement patterns of these hosts.
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Borrelia/genética , Ixodes/microbiologia , Doença de Lyme/microbiologia , Animais , Doenças das Aves/microbiologia , Europa (Continente) , Humanos , Tipagem de Sequências Multilocus/métodos , Aves Canoras/microbiologiaRESUMO
We genetically analysed malaria parasites (Protozoa) in three Mediterranean blue tit (Cyanistes caeruleus) populations from central Spain. A total of 853 breeding individuals were screened for parasites of the genera Plasmodium and Haemoproteus using a very efficient polymerase chain reaction approach that amplifies a partial segment of the mitochondrial cytochrome b gene of these parasites. We have found six lineages of Plasmodium (SGS1, GRW11, COLL1, DELURB4, GRW04 and BLUTI10) parasitizing the studied populations but we did not detect any infection by Haemoproteus. One of the detected lineages (BLUTI10) has not been previously described in any bird species and this is the first study recording lineages DELURB4 and GRW04 in blue tits. SGS1 (belonging to the morphospecies Plasmodium relictum) was the most frequent lineage (overall prevalence, 24 %), whereas the other lineages showed a much lower prevalence (<4 %). Only a small proportion (12.2 %) of positive amplifications of the most common lineage (SGS1) was detected in blood smears using light microscopy and infection intensities were very low (mean ± SE, 2.0 ± 1.4 parasites/2,000 erythrocytes). We have also found strong inter-population variability in prevalence patterns (12-41 % for lineage SGS1), suggesting important differences in parasite transmission rates among the geographically close studied localities.
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Variação Genética , Haemosporida/classificação , Haemosporida/genética , Malária Aviária/parasitologia , Passeriformes/parasitologia , Animais , Análise por Conglomerados , Citocromos b/genética , Haemosporida/isolamento & purificação , Proteínas Mitocondriais/genética , Dados de Sequência Molecular , Parasitos , Filogenia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , EspanhaRESUMO
OBJECTIVES: The purpose of this study was to assess cranial base and maxillary growth in patients with Class II-type I malocclusions when treated with Frankel' s functional regulator (FR-1b). STUDY DESIGN: The treatment group was made up of 43 patients that were divided into two groups: prepubescent (n: 28), and pubescent (n: 15). The control group included 40 patients who did not receive any kind of treatment and were likewise divided into a prepubescent group (n: 19), and a pubescent group (n: 21). A computerized cephalometric study was carried out and superimpositions were done in order to assess the antero-posterior, vertical and rotational movement of the maxilla. RESULTS: The results indicate that anterior cranial length is not affected by the regulator but the cranial deflection of the treatment group was diminished. Although a slight counterclockwise rotation effect on the upper jaw was observed due to treatment, no growth restriction of the maxilla in a vertical or antero-posterior direction was observed compared to other non-treated Class II-type I malocclusion patients. CONCLUSION: The functional regulator does not have any effect on anterior cranial length, but it does affect the angulation of the cranial base. According to our results, the appliance has demonstrated a flattening effect of the cranial base (p<0.05) in the treated sample. The functional regulator induces counterclockwise rotation rather than vertical or sagittal changes in the maxilla.
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Má Oclusão Classe II de Angle/terapia , Maxila/crescimento & desenvolvimento , Aparelhos Ortodônticos Funcionais , Base do Crânio/crescimento & desenvolvimento , Adolescente , Cefalometria , Criança , Feminino , Humanos , Masculino , Estudos RetrospectivosRESUMO
OBJECTIVES: The purpose of this study was to assess mandibular growth in patients with Class II division 1 malocclusions when treated with Fränkel's functional regulator 1b. STUDY DESIGN: The treatment group was made up of 43 patients that were divided into two groups: prepubescent (n:28), and pubescent (n:15). The control group included 40 patients who did not receive any kind of treatment and were likewise divided into a prepubescent group (n:19), and a pubescent group (n:21). A computerized cephalometric study was carried out and superimpositions were done in order to assess the antero-posterior, vertical and rotational movements of the mandible. A two-way ANOVA with interaction was done to compare the changes between the control group and the treatment group, while the Student t for independent samples was used to compare each age group. RESULTS: The Gnathion and Gonion points showed significant differences in the whole sample (p<0.001) as well as in the prepubescent (p<0.001) and pubescent groups (p<0.05). Rotational changes of the mandible measured using the facial axis and mandibular plane showed no statistical differences between both groups (p>0.05). CONCLUSION: The results show that the FR produces vertical orthopedic growth in the mandible but not horizontal growth compared to non-treated Class II-type I malocclusion patients. No rotational changes were found in the mandible, but we did record mandibular growth along the inclination of the facial axis.
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Má Oclusão Classe II de Angle/terapia , Mandíbula/crescimento & desenvolvimento , Aparelhos Ortodônticos Funcionais , Adolescente , Criança , Feminino , Humanos , MasculinoRESUMO
Insectivorous birds rely on a short period of food abundance to feed their young; they must time their reproduction to match the timing of Lepidoptera larvae, their main prey. Apart from the net result (i.e. birds are timed or mistimed with respect to the food's peak), an important aspect is the possible influence of other factors, such as the seasonality of the environment or the abundance and diversity of species contributing to the caterpillar peak, on birds' phenology and their ability to cope well with unpredictable food supplies. In a 2-year study, we explored the seasonal variation of nestling diet in Mediterranean blue tits Cyanistes caeruleus and how reproductive parameters (nestling condition, provisioning rates) are affected by the phenology and composition of food. We also examined the influence of the synchrony between offspring needs and caterpillar peak in shaping the composition of the nestlings' diet. We found that the effect of synchrony on nestling condition varied between years which may be partially due to differences in food peak attributes. The adequacy of birds' timing in relation to prey phenology affected foraging decisions; those birds that were not able to correctly adjust their timing were forced to rely on less preferred prey (tortricids). In this sense, we found that relative contribution of tortricids (smaller caterpillars but easier to get) and noctuids (preferred prey but more difficult to find) to the diet influenced nestling condition and parental provisioning effort; parents performed fewer feeding events and reared heavier nestlings as the contribution of noctuids to the diet increased. The relationship between the proportion of caterpillars and nestling mass was curvilinear, whereas that parameter was negatively affected by the percentage of pupae. Our results show how changes in diet composition may contribute to explain the effect of mismatching on birds' breeding performance.
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Comportamento Alimentar , Preferências Alimentares , Passeriformes/fisiologia , Animais , Dieta , Larva/crescimento & desenvolvimento , Mariposas/crescimento & desenvolvimento , Densidade Demográfica , Comportamento Predatório , Estações do Ano , Comportamento Sexual Animal , Fatores de TempoRESUMO
BACKGROUND: Currently, we are beginning to observe a stabilisation and even a decrease in breast cancer mortality in the world, which may be related, among other reasons, to breast cancer screening. METHODS: The objective of this study was to analyse the different reasons why women do not participate in the Breast Cancer Early Detection Programme in Extremadura (Spain) and to discuss the results, offering possible tools to improve the screening programs. This is an observational, descriptive, cross-sectional and retrospective study. A questionnaire with 14 questions was carried out by telephone or mail. RESULTS: A total of 3970 questionnaires were collected. However, only 2507 were valid. A total of 70.36% of young and educated women underwent mammographic controls. The type of women who did not attend the screening programme appointment corresponded to a woman of approximately 60 years of age, with no formal studies, married, with children, who does not work outside their home and who lived in the health area of Badajoz. Among the main reasons for not going to the appointment, 53.9% of the women surveyed indicated that they had check-ups with their gynaecologist, and this specialist referred them for a mammograph. These women were younger and have a higher level of education. Women with a lower educational level and older women did not have any mammography done and did not undergo screening. They indicated that they did not go to the appointment because they were afraid of having a mammography (44%) or because they did not receive the appointment in time (31.6%). A total of 26.9% of the women who did not attend the appointment for other reasons stated that they had problems in attending because they had a physical limitation (dependency). CONCLUSIONS: Women who did not participate in the breast cancer screening programme in Extremadura had low educational levels and were older women. Specifically, fear of having a mammogram was the main argument raised by these women. In addition, a small group stated that they did not consider mammography to be useful. At present and in the future, good quality screening programs must be carried out to contribute to the reduction in breast cancer mortality. Furthermore, enhancing the participation of women is essential to increase the attendance rate and, therefore, the success of the screening programmes.
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The spatial patterns of the variability of the appearance dates of the honey bee Apis mellifera L. (Hymenoptera: Apidea) and the small white Pieris rapae (L.) (Lepidoptera: Pieridae) were investigated in Spain. A database of more than 7,000 records of the dates of the first spring sightings of each species in more than 700 localities from 1952-2004 was used. Phenological data were related to spatial, topographical, climate, land use, and vegetation productivity explanatory variables by means of multiple regression models in order to search for the environmental mechanisms underlying the observable phenological variability. Temperature and altitudinal spatial gradients accounted for most of the spatial variability in the phenology of the studied species, while vegetation productivity and land use had low relevance. In both species, the first individuals were recorded at those sites with warmer springs and dry summers, at low altitudes, and not covered with dry farming (i.e., cereal crops). The identity and magnitude of the effect of the variables were almost identical for both species and closely mirrored spatial temperature gradients. The best explanatory models accounted for up to half of the variability of appearance dates. Residuals did not show a spatial autocorrelation, meaning that no other spatially structured variable at our working resolution could have improved the results. Differences in the spatial patterns of phenology with regard to other taxa, such as arrival dates of migratory birds, suggest that spatial constraints may play an essential role in the phenological matching between trophic levels.
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Abelhas , Borboletas , Ecossistema , Animais , Geografia , Dinâmica Populacional , Estações do Ano , EspanhaRESUMO
The general hypothesis of mate choice based on non-additive genetic traits suggests that individuals would gain important benefits by choosing genetically dissimilar mates (compatible mate hypothesis) and/or more heterozygous mates (heterozygous mate hypothesis). In this study, we test these hypotheses in a socially monogamous bird, the blue tit (Cyanistes caeruleus). We found no evidence for a relatedness-based mating pattern, but heterozygosity was positively correlated between social mates, suggesting that blue tits may base their mating preferences on partner's heterozygosity. We found evidence that the observed heterozygosity-based assortative mating could be maintained by both direct and indirect benefits. Heterozygosity reflected individual quality in both sexes: egg production and quality increased with female heterozygosity while more heterozygous males showed higher feeding rates during the brood-rearing period. Further, estimated offspring heterozygosity correlated with both paternal and maternal heterozygosity, suggesting that mating with heterozygous individuals can increase offspring genetic quality. Finally, plumage crown coloration was associated with male heterozygosity, and this could explain unanimous mate preferences for highly heterozygous and more ornamented individuals. Overall, this study suggests that non-additive genetic traits may play an important role in the evolution of mating preferences and offers empirical support to the resolution of the lek paradox from the perspective of the heterozygous mate hypothesis.
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Evolução Biológica , Heterozigoto , Comportamento Sexual Animal/fisiologia , Aves Canoras/genética , Aves Canoras/fisiologia , Animais , Feminino , Homozigoto , Masculino , Reprodução/genética , Reprodução/fisiologiaRESUMO
1. We test the consequences, in terms of breeding success and parental effort, of eggshell pigmentation pattern in a hole-nesting bird, the blue tit Cyanistes caeruleus that lays eggs asymmetrically speckled with reddish spots (maculated eggs). 2. We assess the effect of distribution of spots (pigment 'spread') and spot size and pigment intensity (pigment 'darkness') on eggshell physical properties and breeding parameters concerning nestling condition, investment of parents in offspring care and reproductive output in two different habitat types: a deciduous oakwoodland and an evergreen forest. 3. Blue tit clutches with more widely distributed spots showed a thicker eggshell, a shorter incubation period, a lesser amount of mass loss per day and a higher hatching probability than those with spots forming a 'corona' ring. While eggs with larger and darker (more pigment intensity) spots showed a thicker eggshell and a shorter incubation period. In the light of 'signal function hypothesis', these egg traits may reflect female health status and, consequently, this could affect male parental effort. 4. Here we show supports for some of the necessary assumptions of this hypothesis. We found a positive relationship between egg pigment 'spread' and male but not female provisioning rates per day. On the other hand, pigment 'darkness' of blue tits' clutches was positively related to female tarsus length, while pigment 'spread' was positively related to clutch size, male body mass and nestling tarsus length. Our study shows that eggshell pigment 'spread' can be used as an indicator of clutch quality. Further investigations are needed to understand the role of calcium availability as possible causal agent of deviant eggs and its relation to the maculation phenomenon.
Assuntos
Passeriformes/fisiologia , Pigmentação/fisiologia , Reprodução/fisiologia , Zigoto/fisiologia , Animais , Peso Corporal/fisiologia , Cruzamento , Tamanho da Ninhada/fisiologia , Feminino , Masculino , Tarso Animal/anatomia & histologia , Fatores de TempoRESUMO
Avian timing of reproduction is strongly affected by ambient temperature. Here we show that there is an additional effect of sunspots on laying date, from five long-term population studies of great and blue tits (Parus major and Cyanistes caeruleus), demonstrating for the first time that solar activity not only has an effect on population numbers but that it also affects the timing of animal behaviour. This effect is statistically independent of ambient temperature. In years with few sunspots, birds initiate laying late while they are often early in years with many sunspots. The sunspot effect may be owing to a crucial difference between the method of temperature measurements by meteorological stations (in the shade) and the temperatures experienced by the birds. A better understanding of the impact of all the thermal components of weather on the phenology of ecosystems is essential when predicting their responses to climate change.
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Comportamento de Nidação , Oviparidade , Passeriformes/fisiologia , Sistema Solar , Animais , Feminino , Países Baixos , Temperatura , Fatores de TempoRESUMO
The extent of inbreeding depression and the magnitude of heterozygosity-fitness correlations (HFC) have been suggested to depend on the environmental context in which they are assayed, but little evidence is available for wild populations. We combine extensive molecular and capture-mark-recapture data from a blue tit (Cyanistes caeruleus) population to (1) analyze the relationship between heterozygosity and probability of interannual adult local recruitment and (2) test whether environmental stress imposed by physiologically suboptimal temperatures and rainfall influence the magnitude of HFC. To address these questions, we used two different arrays of microsatellite markers: 14 loci classified as neutral and 12 loci classified as putatively functional. We found significant relationships between heterozygosity and probability of interannual local recruitment that were most likely explained by variation in genomewide heterozygosity. The strength of the association between heterozygosity and probability of interannual local recruitment was positively associated with annual accumulated precipitation. Annual mean heterozygosity increased over time, which may have resulted from an overall positive selection on heterozygosity over the course of the study period. Finally, neutral and putatively functional loci showed similar trends, but the former had stronger effect sizes and seemed to better reflect genomewide heterozygosity. Overall, our results show that HFC can be context dependent, emphasizing the need to consider the role of environmental heterogeneity as a key factor when exploring the consequences of individual genetic diversity on fitness in natural populations.
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There is little direct evidence of the fitness effects of changes in malaria gametocyte sex ratio. Gametocyte sex ratios in haemospororin parasites (phylum Apicomplexa) are usually female skewed. However, in some cases and especially in Haemoproteus parasites, less female-biased and even male-biased sex ratios are encountered. The 'fertility insurance hypothesis' tries to explain these biases as an evolutionary strategy to facilitate gamete encounter. Thus, the hypothesis predicts that, if there is a reduction in gametocyte density (intensity of infection) or other factors preventing gametes from meeting, a change to a higher proportion of male gametocytes may be favoured. By contrast, a change in sex ratio may be caused by other non-adaptive mechanisms, for example differential survival of the gametocytes of each sex. We study within-host changes in Haemoproteus majoris sex ratios following an experimental reduction in the density of the parasites in the blood in a breeding population of blue tits (Parus caeruleus). Medication with the antimalarial drug primaquine induced a significant reduction in Haemoproteus gametocyte infection intensity in two different breeding seasons and under two different doses of medication. Sex ratios became male skewed following the experimental treatment in agreement with the predictions of the 'fertility insurance' hypothesis. Also in support of the hypothesis, a significant change towards male-biased sex ratios emerged for non-medicated birds in one year, probably owing to the natural immune reduction of the density of the parasites in the blood. The alternative possibility that changes are caused by different lifespans of gametocytes is not supported by changes in sex ratios in control hosts, where new production and release of gametocytes occur.
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Doenças das Aves/parasitologia , Haemosporida/fisiologia , Malária Aviária , Modelos Biológicos , Razão de Masculinidade , Análise de Variância , Animais , Aves , Feminino , Fertilidade/fisiologia , Haemosporida/citologia , Interações Hospedeiro-Parasita , Longevidade/fisiologia , Masculino , Primaquina , EspanhaRESUMO
Advances in the phenology of organisms are often attributed to climate change, but alternatively, may reflect a publication bias towards advances and may be caused by environmental factors unrelated to climate change. Both factors are investigated using the breeding dates of 25 long-term studied populations of Ficedula flycatchers across Europe. Trends in spring temperature varied markedly between study sites, and across populations the advancement of laying date was stronger in areas where the spring temperatures increased more, giving support to the theory that climate change causally affects breeding date advancement.
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Clima , Periodicidade , Reprodução/fisiologia , Aves Canoras/fisiologia , Animais , Europa (Continente) , Geografia , Modelos Lineares , Estações do Ano , TemperaturaRESUMO
Post-nuptial moult and reproductive success were studied in relation to timing of breeding in blue tits, Parus caeruleus, breeding in southern Europe. A group of experimentally delayed pairs was created by removing first clutches, thereby inducing late repeat clutches. Reproductive success and post-nuptial moult of delayed pairs were compared with both control pairs that bred early and unmanipulated late-breeding pairs. Delayed pairs fledged fewer young and with a lower body mass than control pairs. However, the number of fledged young and fledgling mass did not differ between delayed and late-breeding pairs. These results were more consistent with the date hypothesis, and it is concluded that the timing of breeding and reproductive success may be causally related in the blue tit. This study reveals a harmful effect of relaying on female body mass at the end of the nestling period. Therefore, females apparently pay the costs of relaying, since a reduction in body mass during the nestling period may be accompanied by a lowered survival probability. Delayed and late-breeding males often began moulting while still feeding young, but neither control males nor females from the three study groups did so. These results support the view that timing-related energy constraints on breeding may be important causes of a seasonal decline in reproductive success at different latitudes.
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The relationship between hemoparasite infection (measured just after egg laying) and primary reproductive output (laying date, clutch size and egg volume) was studied in female pied flycatchers, Ficedula hypoleuca, of different ages (2 years old vs. 4 or more years old). The hemoparasite (Haemoproteus balmorali and Trypanosoma spp.) prevalence increased with advancing female age. H. balmorali-infected females initiated egg laying earlier and laid larger clutches. There was no evidence that infected females laid smaller eggs or had a lower body mass after egg laying than non-infected ones. Only for H. balmorali-infected females was there an increase in clutch size between age groups. The present results suggest that primary reproductive output of females will depend on their health-dependent residual reproductive value. Only old females may be able to control a chronic or latent infection by hemoparasites and thereby invest more heavily in reproduction than younger but experienced females. Alternatively, high hemoparasite prevalence may be the cause of increased female primary reproductive output in old females.
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Oncogenic osteomalacia is an uncommon syndrome characterized by phosphaturic tumours that produce mineral metabolism abnormalities. Head and neck is the second most frequent location of these tumours. We describe a case of a phosphaturic mesenchymal tumour in the infratemporal fossa that caused oncogenic osteomalacia, resolved by means of surgical excision.
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Neoplasias de Cabeça e Pescoço/complicações , Hipofosfatemia Familiar/complicações , Feminino , Humanos , Neoplasias Hepáticas/complicações , Mesenquimoma/complicações , Pessoa de Meia-Idade , Neoplasias de Tecido Conjuntivo/etiologia , Osteomalacia , Síndromes Paraneoplásicas , ZigomaRESUMO
In the present study, large scale geographical variation in the occurrence of organohalogenated pollutants (OHPs) was investigated throughout Europe using eggs of a terrestrial resident passerine species, the blue tit (Cyanistes caeruleus). Blue tit eggs from 10 sampling locations, involving suburban, rural and remote areas, in 7 European countries were collected and analysed. Sum polychlorinated biphenyl (PCB) levels ranged from 150ng/g lipid weight (lw) to 2003ng/g lw. Sum polybrominated diphenyl ethers (PBDEs) ranged from 3.95ng/g lw to 114ng/g lw. As expected, PCB and PBDE concentrations were significantly higher in the sampled suburban locations compared to the rural and remote locations. Sum organochlorine pesticides (OCPs) ranged from 122ng/g lw to 775ng/g lw. OCP concentrations were, against the expectations, found to be lower in the rural sampling locations compared to the other locations. Contamination profiles of PCBs, PBDEs and OCPs differed also among the sampling locations, which may be due to local contamination sources. Finally, we compared the results of this study with previously reported OHP concentrations in the eggs of a closely related species, the great tit (Parus major), from the same sampling locations in Europe. We found no differences in concentrations between the species. In addition, we found a significant, positive correlation between the sum PCB concentrations in blue tit eggs and great tit eggs, suggesting similar exposure pathways, mechanisms of accumulation and maternal transfer of PCBs. In conclusion, our results suggest the usefulness of eggs from passerine birds as a biomonitoring tool for OHPs on a large geographical scale.
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Monitoramento Ambiental/métodos , Poluentes Ambientais/metabolismo , Éteres Difenil Halogenados/metabolismo , Hidrocarbonetos Clorados/metabolismo , Óvulo/metabolismo , Passeriformes , Bifenilos Policlorados/metabolismo , Animais , Europa (Continente) , Praguicidas/metabolismoRESUMO
Large-scale studies are essential to assess the emission patterns and spatial distribution of organohalogenated pollutants (OHPs) in the environment. Bird eggs have several advantages compared to other environmental media which have previously been used to map the distribution of OHPs. In this study, large-scale geographical variation in the occurrence of OHPs, such as polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and organochlorine pesticides (OCPs), was investigated throughout Europe using eggs of a terrestrial residential passerine species, the great tit (Parus major). Great tit eggs from 22 sampling sites, involving urban, rural and remote areas, in 14 European countries were collected and analysed (5-8 eggs per sampling site). The environmentally most important congeners/compounds of the analysed pollutants were detectable in all sampling locations. For PCBs, PBDEs and OCPs, no clear geographical contamination pattern was found. Sum PCB levels ranged from 143 ng/g lipid weight (lw) to 3660 ng/g lw. As expected, PCB concentrations were significantly higher in the sampled urban compared to the remote locations. However, the urban locations did not show significantly higher concentrations compared to the rural locations. Sum PBDEs ranged from 4.0 ng/g lw to 136 ng/g lw. PBDEs were significantly higher in the urbanized sampling locations compared to the other locations. The significant, positive correlation between PCB and PBDE concentrations suggests similar spatial exposure and/or mechanisms of accumulation. Significantly higher levels of OCPs (sum OCPs ranging from 191 ng/g lw to 7830 ng/g lw) were detected in rural sampling locations. Contamination profiles of PCBs, PBDEs and OCPs differed also among the sampling locations, which may be due to local usage and contamination sources. The higher variance among sampling locations for the PCBs and OCPs, suggests that local contamination sources are more important for the PCBs and OCPs compared to the PBDEs. To our knowledge, this is the first study in which bird eggs were used as a monitoring tool for OHPs on such a large geographical scale.